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Flavor-Changing Top Quark Rare Decays in the Littlest Higgs Model with T-Parity

Hou Hong-Sheng
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Abstract

We analyze the rare and flavor changing decay of the top quark into a charm quark and a gauge boson in the littlest Higgs model with T-parity (LHT). We calculate the one-loop level contributions from the T-parity odd mirror quarks and gauge bosons. We find that the decay $t\to c V, (V=g,γ,Z)$ in the LHT model can be significantly enhanced relative to those in the Standard Model. Our numerical results show that the top quark FCNC decay can be as large as $Br(t\to cg)\sim 10^{-2}$, $Br(t\to cZ)\sim 10^{-5}$ and $Br(t\to cγ)\sim 10^{-7}$ in the favorite parameter space in the LHT model.

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Hou Hong-Sheng. 2007-03-06. Flavor-Changing Top Quark Rare Decays in the Littlest Higgs Model with T-Parity. https://doi.org/10.1103/physrevd.75.094010

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